The tube is pretty dire, I remember once (pre-children), watching a woman with baby in a back carrier getting on the train...the mother got on fine, the doors closed before the baby was in though, I slammed on the emergency alarm thing.... I was shaking so much afterwards, the baby was thankfully unaware, as the doors opened again, but the mum was really grateful, all the other passengers were pretty shaken too.
There's also a family friend who's ds got off the train with his dad. The boy was wearing one of those coats that have little ties at the hood, his tie got caught in the train doors and the train left, friends ds couldn't get the coat off and passed away.... apparantly the obstruction in the doors was so small it didn't stop the train.....